e1000e: convert enums of register offsets and move #defines to regs.h

There are enough register offsets to warrant being in their own header
file, and doing so logically separates them from other header file content.
They have been converted from an enumerated data type to #defines as is
done in all the other Intel wired ethernet drivers.
Signed-off-by: Bruce Allan <bruce.w.allan@intel.com>
Tested-by: Aaron Brown <aaron.f.brown@intel.com>
Signed-off-by: Jeff Kirsher <jeffrey.t.kirsher@intel.com>

drivers/net/ethernet/intel/e1000e/netdev.c

@@ -86,18 +86,6 @@ struct e1000_reg_info {
 	char *name;
 };
 
-#define E1000_RDFH	0x02410	/* Rx Data FIFO Head - RW */
-#define E1000_RDFT	0x02418	/* Rx Data FIFO Tail - RW */
-#define E1000_RDFHS	0x02420	/* Rx Data FIFO Head Saved - RW */
-#define E1000_RDFTS	0x02428	/* Rx Data FIFO Tail Saved - RW */
-#define E1000_RDFPC	0x02430	/* Rx Data FIFO Packet Count - RW */
-
-#define E1000_TDFH	0x03410	/* Tx Data FIFO Head - RW */
-#define E1000_TDFT	0x03418	/* Tx Data FIFO Tail - RW */
-#define E1000_TDFHS	0x03420	/* Tx Data FIFO Head Saved - RW */
-#define E1000_TDFTS	0x03428	/* Tx Data FIFO Tail Saved - RW */
-#define E1000_TDFPC	0x03430	/* Tx Data FIFO Packet Count - RW */
-
 static const struct e1000_reg_info e1000_reg_info_tbl[] = {
 
 	/* General Registers */